Middle school students can understand the principles of how an electric motor works by understanding how electromagnets and magnetic fields work. They can create electromagnetism by using some simple household items. Wrapping loops of wire around a nail and connecting it to a battery will create magnetism and a magnetic field. The nail will have a north and south pole, or a positively and negatively charged end, when connected with the battery, and it will perform just like a traditional magnet.
Balloons fascinate middle school students. Charging a balloon with static electricity can help them understand common electromagnetic concepts. The students need inflated balloons, along with string, steel cans and wool fabric. Rubbing the balloons against the wool, then trying to push them together, can help them understand how electromagnets work. They can also rub the balloons on their hair then hold the balloons close to a steel can. The balloons will be attracted to the cans.
Magnets are converted into magnetic strips and used to store information. In audio and video tapes, the sound and images are stored on the magnetic coating of the tape. The tape, coated with a metal powder, changes with fluctuations in the magnetic field. Middle school students can try placing audio or video tapes near a strong magnet and observe that the data encoded inside the tape is destroyed. This experiment demonstrates how magnetic fields interact with each other.
Middle school students can try an experiment with a compass and an electrical current to understand electromagnetism and electrical fields. If a wire is connected to a battery so that a current flows through the wire, then the wire is held above a compass, the compass needle will align itself with the magnetic field in the wire rather than pointing toward true North. The electrical current flowing through the wire creates a magnetic field around it. As students watch the effects of the electrical current on the compass needle, they will understand the power of something that they cannot see.